995 resultados para Alphandery (18..-19..) -- Portraits


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<正> 中国科学院水生生物研究所第一研究室鱼类生态的研究人员,于1982年11月1~2日(水温18~19℃),解剖了30尾从宜昌十里红江段刚捕起的铜鱼,发现其中14尾鱼的肠管中有中华鲟的卵,胚胎已发育到囊胚期和原肠期.据推算距受精时间约为17~25小时.11月5~6日在同一地点,又解剖到肠管中含有中华鲟卵的铜鱼7尾,卵子发育至卵裂期,距受精时间约数小时,可判定与11月1~2日所发现的鲟卵不是同批产出的.

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本发明公开了一种用于光纤光栅切趾的可调三角形共轭振幅模板,其特征在于,包括一共轭振幅板(19),上有正切趾光阑(17)和反切趾光阑(18),该共轭振幅板(19)正面安装有上挡板(20)和下挡板(21),上挡板(20)和下挡板(21)分别在上挡板导轨(25)和下挡板导轨(26)的导引下上下滑动,该共轭振幅板(19)背面安装有左栅长定位板(22)和右栅长定位板(23),左栅长定位板(22)和右栅长定位板(23)在栅长定位板导轨(31)的导引下左右滑动。本发明同时公开了一种利用可调三角形共轭振幅模板实现光纤光栅切趾的方法。本发明适应性好,灵活性强,工艺简单。

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Three-terminal ballistic junctions (TBJs) are fabricated from a high-mobility InP/In0.75Ga0.25As heterostructure by electron-beam lithography. The voltage output from the central branch is measured as a function of the voltages applied to the left and right branches of the TBJs. The measurements show that the TBJs possess an intrinsic nonlinearity. Based on this nonlinearity, a novel room-temperature functional frequency mixer and phase detector are realized. The TBJ frequency mixer and phase detector are expected to have advantages over traditional circuits in terms of simple structure, small size and high speed, and can be used as a new type of building block in nanoelectronics.

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Diphasic silicon films (nc-Si/a-Si:H) have been prepared by a new regime of plasma enhanced chemical vapour deposition in the region adjacent of phase transition from amorphous to microcrystalline state. Comparing to the conventional amorphous silicon (a-Si:H), the nc-Si/a-Si:H has higher photoconductivity (sigma(ph)), better stability, and a broader light spectral response range in the longer wavelength range. It can be found from Raman spectra that there is a notable improvement in the medium range order. The blue shift for the stretching mode and red shift for the wagging mode in the IR spectra also show the variation of the microstructure. By using this kind of film as intrinsic layer, a p-i-n junction solar cell was prepared with the initial efficiency of 8.51 % and a stabilized efficiency of 8.01% (AM 1.5, 100 mw/cm(2)) at room temperature. (c) 2006 Published by Elsevier B.V.

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本书是在国家自然科学基金委员会信息科学部的支持下,邀请了三十余位工作在半导体研究领域第一线的知名专家撰写而成的。本书系统介绍了当前国际、国内半导体科学和技术各个领域,包括半导体材料的生长、物理问题、重要实验和理论结果、器件结构和应用等方面的基础知识、研究现状、发展趋势和有待解决的关键问题。 本书适合从事半导体研究和教学的大学教师、科技工作者、工程技术人员、研究生、本科生以及科技管理部门有关工作人员和管理专家阅读和参考。

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Diphasic silicon films (nc-Si/a-Si:H) have been prepared by a new regime of plasma enhanced chemical vapour deposition in the region adjacent of phase transition from amorphous to microcrystalline state. Comparing to the conventional amorphous silicon (a-Si:H), the nc-Si/a-Si:H has higher photoconductivity (sigma(ph)), better stability, and a broader light spectral response range in the longer wavelength range. It can be found from Raman spectra that there is a notable improvement in the medium range order. The blue shift for the stretching mode and red shift for the wagging mode in the IR spectra also show the variation of the microstructure. By using this kind of film as intrinsic layer, a p-i-n junction solar cell was prepared with the initial efficiency of 8.51 % and a stabilized efficiency of 8.01% (AM 1.5, 100 mw/cm(2)) at room temperature. (c) 2006 Published by Elsevier B.V.

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在介绍汽车检测线系统的基础上,探讨了实时网络监控在汽车检测线上的应用,为了克服检测过程存在较多人为因素的缺点和解决汽车检测场社会化引起的监管问题,提出了通过控制摄像头多角度拍摄监控照片对被检车辆进行身份认证的新方法,该方法可以方便异地监控端实时了解汽车检测线上的各类检测情况,并且有助于保证检测过程的真实有效性

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首次从野桂花(Osmanthus yunnanensis Fr. P. S. Green)地上部分95%乙醇提取物中通过色谱分离得到20个化合物, 其中化合物20为新化合物。基于波谱数据它们被鉴定为(E)-阿魏酸二十烷基酯(1)、β-谷甾醇(2)、羽扇豆醇(3)、齐墩果酸(4)、7-oxo-β-sitosterol(5)、乙酰齐墩果酸(6)、(6′-O-palmitoyl)-sitosterol 3-O-β-D-glucoside(7)、rotundioic acid(8)、地榆糖甙Ⅱ(9)、27-O-(E)-对羟基肉桂酰-28-齐墩果酸(10)、27-O-(Z)-对羟基肉桂酰-28-齐墩果酸(11)、hycandinic acid ester(12)、绿原酸丁酯(13)、4,5-二咖啡酰奎尼酸丁酯(14)、4,5-dihydroxyprenyl caffeate(15)、28-O-β-D-glucopyranosyl rotundioic acid (16)、4-(6-O-caffeoyl-β-D-glucopyranosyloxy)-5-hydroxyprenyl caffeate (aohada-glycoside C, 17)、 4-β-D-glucopyranosyloxy-5-hydroxy-prenyl caffeate (aohada-glycoside A, 18)、β-胡萝卜甙(19)以及3-[O-β-D-(6-O-咖啡酰吡喃葡萄糖)]-甲基-2-烯-γ-内酯 (20)。化合物13、14、15和17有较强的α-葡萄糖甙酶抑制活性。当浓度为1 mg/ml时,它们对α-葡萄糖甙酶的抑制分别为61.5%、95.5%、72.1%、62.6%,活性高于阿卡波糖。 综述了木犀属植物化学成分及1993年以来苯丙素甙类化合物活性研究进展。 Twenty compounds were isolated from the 95% ethanol extract of the aerial parts of Osmanthus yunnanensis Fr. P. S. Green by chromatography for the first time. On the basis of spectral data, they were identified as (E)-ferulic acid eicosyl ester (1), β-sitosterol (2), lupenol (3), oleanolic acid (4), 7-oxo-β-sitosterol (5), acetyloleanolic acid (6), (6′-O-palmitoyl)-sitosterol 3-O-β-D-glucoside (7), rotundioic acid (8), ziyu glycosideⅡ (9), 3β-hydroxy-27-p-(E)-coumaroyloxy-olean-12-en-28-oic acid (10), 3β-hydroxy-27-p-(Z)-coumaroyloxyolean-12-en-28-oic acid (11), hycandinic acid ester (12), chlorogenic acid butyl ester (13), 4,5-di-O-caffeoylquinic acid butyl ester (14), 4,5-dihydroxyprenyl caffeate (15), 28-O-β-D-glucopyranosyl rotundioic acid (16), 4-(6-O-caffeoyl-β-D-glucopyranosyloxy)-5-hydroxyprenyl caffeate (aohada- glycoside C, 17), 4-β-D-glucopyranosyloxy-5-hydroxyprenyl caffeate (aohada- glycoside A, 18), β-daucosterol(19) and 3-[O-β-D-(6-O-caffeoylglucopyranosyl)]- methyl-2-en-γ-lactone (20). Compound 20 is a new one. Compounds 13, 14, 15 and 17 inhibit α-glucosidase with corresponding inhibitory rate of 61.5%, 95.5%, 72.1% and 62.6% at a concentration of 1 mg/ml, higher than acarbose. The chemical studies on Osmanthus genus and bioactivities of phenylpropanoid glycosides were summarized.

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本论文由三章组成。第一章为综述,概述了植物中环烯醚萜类化合物的研究进展;第二和第三章为实验论文,分别报道了唇形科药用植物绵参和蔷薇科药用植物地榆的化学成分研究。 第一章概述了植物中环烯醚萜类化合物的研究成果,主要包括结构类型及药理活性等方面。 第二章包括两个部分。第一部分报道了藏药绵参(Eriophyton wallichii Benth)地上部分甲醇提取物的化学成分。采用正、反相硅胶柱层析等各种分离方法,从中共分离出7个化合物,有6个化合物为首次从该植物中分离得到,分别为β-谷甾醇(1),夏至草苦素(marrubiin,2),乌苏酸(3),cimigoside(4),5-deoxyantirrhinoside(5),8-表马钱子酸葡萄糖苷(8-epiloganic acid,6)和apigenin 7-(6''-p-coumaroyl)glucoside(7)。第二部分,采用高效液相色谱-质谱联用技术对绵参地上部分的甲醇提取物进行了分析,通过标准品对照紫、外光谱分析以及多级质谱分析与文献对照鉴定了8个成分,分别是:8-epiloganic acid(Ⅰ),quercitrin 3-glucoside-7-(6''-p-coumaroyl)glucoside(Ⅱ),ajugoside(I) (Ⅲ),chrysoeriol 7-O-E-p-coumaroyl-3-O-b-D-glucoside(Ⅳ),helichrysoside(Ⅴ),生物碱(Ⅵ),apigenin 2,3-dihydrogen-7-(6''-p-coumaroyl) glucoside(Ⅶ),apigenin 7-(6''-p-coumaroyl) glucoside(Ⅷ)。 第三章报道了中药地榆根部乙醇提取物正丁醇相的化学成分,通过正、反相硅胶柱层析等各种分离方法,从中分离得到8个化合物,分别为3,4¢- O-二甲基逆没食子酸(8),3,3¢,4¢-O-三甲基逆没食子酸(9)和3,4¢-O-二甲基逆没食子酸-4-O-b-D-木糖苷(10),19a-羟基-3-O-(a-L-阿拉伯糖)乌苏酸-28-O-b-D-葡萄糖苷(11), 3b-[(a-L-arabinopyranosyl)oxy]-urs-11,13(18)-dien-28-oic acid b-D- glucopyranosyl ester(13),3-O-a-L-arabinopyranosyl-urs-12,18(19)-dien-28-oic acid b-D-glucopyranosyl ester(14),儿茶素(15),还有一种可能是皂苷11的工作产物(12)。 This dissertation consisted of three chapters. The first chapter elaborated the progress of iridoids occurring in plants. The later two chapters respectively elaborated the chemical constituents of Eriophyton wallichii Benth. and Sanguisorba officinalis L. The first chapter is a review of the research progress of iridoids occurring in plants, which includes their structure and pharmacology. The second chapter consisted of two parts. The first part is about the chemical constituents of methanol extraction from the aerial parts of Eriophyton wallichii Benth. Seven compounds were isolated and identified. Among them, the compounds of marrubiin, ursolic acid, cimigoside, 5-deoxyantirrhinoside, 8-epiloganic acid,apigenin 7-(6''-p-coumaroyl)glucoside were firstly reported in this plant. A HPLC-MSn method was developed for rapid identification of major compounds of Eriophyton wallichii. A total of 8 peaks in the chromatograms were unequivocally determined (peaks 1, 8) or tentatively identified (peaks 2-7) based on the detailed UV and tandem mass spectra analysis. Seven components were identified as 8-epiloganic acid(Ⅰ),Quercitrin 3-glucoside-7-(6''-p-coumaroyl)glucoside(Ⅱ),ajugoside(I)(Ⅲ),Chrysoeriol 7-O-E-p-coumaroyl-3-O-b-D-glucoside(Ⅳ),helichrysoside(Ⅴ),apigenin 2,3-dihydrogen-7-(6''-p-coumaroyl) glucoside(Ⅵ),apigenin 7-(6''-p-coumaroyl) glucoside(Ⅶ)。 The third chapter elaborated the chemical constituents of methanol extraction from Sanguisorba officinalis L, eight compounds were isolated from this plant by repeat column chromatography over silica gel. These compounds were identified as 3,4′-O-dimethylellagic acid, 3,3′,4′-O-trimethylellagic acid, 3,4′-O-dimethylellagic acid-4-O-b-D-xyloside, 3b-O-a-L-arabinopyranosyl-19a- hydroxyl-urs-12-en-28-oic acid 28-b-D-glucopyranoside, 3b-[(a-L-arabinopyranosyl)oxy]-urs-11,13(18)-dien- 28-oic acid b-D-glucopyranosyl ester,3-O-a-L–arabinopyranosyl-urs-12,18(19) -dien-28-oic acid b-D-glucopyranosyl ester, catechin.

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本文对禄春安息香(Styrax macranthus)种子和攀援孔药花(Porandra scandens)全草的化学成分进行了研究,共获得30个化合物,其中2个为新化合物。 从禄春安息香种子95%乙醇提取物中分离并鉴定了12个化合物,其中2个新化合物鉴定为3-[7-methoxy-2-(3,4-methylenedioxy phenyl) benzofuran-5-yl] propyl 3-[7-methoxy-2-(3,4-methylenedioxyphenyl)benzofuran-5-yl] propanoate (1) 和去甲氧基-egonol-龙胆双糖甙 (2);已知化合物分别为2-(3,4-二氧亚甲基苯基)-5-甲酰基-7-甲氧基-苯并呋喃 (3)、egonol (4)、去甲氧基-egonol (5)、去甲基-egonol (6)、egonol-葡萄糖甙 (7)、egonol-龙胆双糖甙 (8)、egonol-龙胆三糖甙 (9)、豆甾醇 (10)、二十四烷酸 1-甘油酯 (11) 和胡萝卜甙 (12)。生物活性测试发现,化合物2具有促进雌激素E2合成的作用。 从攀援孔药花全草95%乙醇提取物中分离并鉴定了19个化合物:(2S,3S,4R)-2-[(2R)-2-羟基-二十一烷酰基氨基]-二十一烷-1,3,4-三醇 (13)、(2S,3S,4R)–2–二十四烷酰基氨基-十八烷-1,3,4-三醇 (14)、胡萝卜甙 (12)、β-谷甾醇 (15)、(20S,22E,24R)-5α,8α-表二氧-麦角甾-6,22-二烯-3β-醇 (16)、6β-羟基-豆甾-4-烯-3-酮 (17)、十六烷酸 1-甘油酯 (18)、桦木酸 (19)、大黄素 (20)、二十二烷酸 1-甘油酯 (21)、对羟基苯甲醛 (22)、十七烷酸 1-甘油酯 (23)、金色酰胺醇乙酸酯(24)、十九烷酸 1-甘油酯 (25)、棕榈酸 (26)、(E)-p-香豆酸 (27)、(22E,24S)-24-麦角甾醇-7,22-二烯-3β,5α,6β-三醇 (28)、2-去氧-β-蜕皮激素 (29)和auranamide (30)。 综述了近十年来发现的2-芳基苯并呋喃类新木脂素的结构特征、来源、生物活性和化学全合成。 Phytochemical investigation on the seeds of Styrax macranthus and the whole plants of Porandra scandens led to the isolation of thirty compounds, two of which were new ones. Two new 2-aryl benzofuran derivatives, 3-[7-methoxy-2-(3,4-methylenedioxy phenyl) benzofuran-5-yl]propyl 3-[7-methoxy-2-(3,4-methylenedioxyphenyl)benzo furan-5-yl]propanoate (1) and demethoxy egonol gentiobioside (2), were isolated from the 95% aqueous ethanolic extract of the seeds of Styrax macranthus, together with 7-methoxy-2-(3,4-methylenedioxyphenyl) benzofuran-5-carbaldehyde (3), egonol (4), demethoxy egonol (5), demethyl egonol (6), egonol glucoside (7), egonol gentiobioside (8), egonol gentiotrioside (9), stigmasterol (10), 2,3-dihydroxypropyl tetracosoate (11), and daucosterol (12). In vitro test, compound 2 promote the synthesis of estrogen E2. Nineteen compounds were isolated from the 95% aqueous ethanolic extract of the whole plant of Porandra scandens for the first time. Their structures were identified as (2S,3S,4R)-2-[(2R)-2-hydroxy-heneicosanoylamino]-1,3,4- heneicosanetriol (13), (2S,3S,4R)-2-tetracosanoylamino-1,3,4-octadecanetriol (14), daucosterol (15), β-sitosterol (12), (20S,22E,24R)-5α,8α-epidioxy-ergosta-6,22-diene- 3β-ol (16), 6β-hydroxylstigmast-4-en-3-one (17), 1-glycerol-1-hexadecoate (18), betulinic acid (19), emodin (20), 1-glycerol-1-docosoate (21), p-hydroxybenzaldehyde (22), 1-glycerol-1-heptadecoate (23), aurantiamide acetate (24), 1-glycerol-1- nonadecoate (25), palmatic acid (26), (E)-p-coumaric acid (27), (22E,24S)- 24-metbylcbolesta-7,22-diene-3β,5α,6β-triol (28), 2-deoxycrustecdysone (29), and auranamide (30). The characteristic, natural resource, bioactivity, and the total synthesis of 2-aryl benzofurans were reviewed.